In a dye diffusion transfer recording system (hereinafter also referred to as a sublimation transfer recording system), a heat-sensitive transfer sheet (hereinafter simply also referred to as an ink sheet) containing a colorant (hereinafter also referred to as a dye) is superposed on a heat-sensitive transfer image-receiving sheet (hereinafter simply also referred to as an image-receiving sheet), and then the heat-sensitive transfer sheet is heated by a thermal head whose exothermic action is controlled by electric signals, in order to transfer the dyes contained in the heat-sensitive transfer sheet to the image-receiving sheet, thereby recording an image information. Three colors: cyan, magenta, and yellow, or four colors which consist of the three colors and black are used for recording a color image by overlapping one color to other, thereby enabling transferring and recording a color image having continuous gradation for color densities.
On the other hand, in recent years, the demands on color images are diversified, and there is a demand for obtaining three-dimensional images conveniently and inexpensively. It has been known that, so as to make a picture, a photograph, or the like being stereoscopically viewed, a lenticular lens (sheet-shaped) formed from semi-cylindrical lenses is attached on a printed picture or photograph correspondingly to the right-side eye and the left-side eye. In order to make the picture, photograph, or the like being stereoscopically viewed with high precision in this technique, it is required that the printed images viewed respectively by the right-side eye and the left-side eye are disposed in correspondence with the positions of the respective lenses of the lenticular lens.
Japanese Patent No. 3609065 discloses an image recording apparatus equipped with a recording unit that records an image on the back side of the lenticular lens sheet, a moving mechanism for moving the recording unit and the lenticular lens sheet relatively to each other, a position detecting unit provided to be contacted with the concave parts and/or convex parts of the lenticular lens sheet, and a recording control unit that controls the recording unit to perform recording while detecting the position of the lenticular lens sheet by means of the position detecting unit.
Japanese Patent No. 3789033 and JP-A-9-300828 (“JP-A” means unexamined published Japanese patent application) discloses a method of producing a lenticular lens sheet printed material, including: preparing a heat transfer sheet provided with a coloring material transfer unit and a white layer transfer unit in area order on the same surface of a substrate film; thermally moving the coloring material from the coloring material transfer unit to the back surface of the lenticular lens sheet by using a heating device; and subsequently thermally transferring the white layer.
JP-A-6-282019 discloses a heat-sensitive transfer recording sheet for stereoscopic photographs, which utilizes the lenticular lens sheet as a substrate and has a dye receptor layer provided on the back side of the lenticular lens sheet.
JP-A-5-131760 and JP-A-2008-155612 disclose a heat-sensitive transfer sheet, in which a hydrophilic dye barrier layer, containing a polyvinylpyrrolidone and a polyvinyl alcohol, is used, as a dye transfer barrier layer, in order to enhance dye transfer efficiency, and a heat-sensitive transfer sheet having, as a dye transfer barrier layer, a subbing layer, containing a copolymer resin of a polyvinylpyrrolidone and a vinyl acetate and colloidal inorganic pigment fine particles as main components, in order to enhance dye transfer efficiency.
In the heat-sensitive transfer image-receiving sheet having a lenticular lens as described above, since stereoscopic images are viewed from the side of the lenticular lens, it is impossible to use an opaque heat-insulating layer (e.g. a heat-insulating layer composed of stretched polyolefin film, or a heat-insulating layer containing a hollow polymer) between a receptor layer and a support. Accordingly, in the case where images are output in a combination of the heat-sensitive transfer image-receiving sheet having a lenticular lens sheet as described above and a heat-sensitive transfer sheet which does not have the heat-insulating layer as described above in order to obtain high density images, this case causes a problem that a ribbon at a black or high-density image section gets wrinkled, since the ribbon is adversely affected by the heat of a thermal head, and resultantly an image defect of the same shape (wrinkle shape) is likely to generate. Further, since images are viewed through the lenticular lens, a new problem has been caused that an image defect (shift of register in color printing) in which yellow, magenta, and cyan images shift becomes easily-noticeable, and resultantly image defects such as shift of register in color printing are likely to generate.